Method of increasing efficiency of a Y strainer and a Y strainer

Abstract

A method of increasing efficiency of a Y strainer and Y strainer modified in accordance with the method. The Y strainer is of the type that has a filter cartridge receiving inflow through one end and outflow through apertures in a peripheral sidewall. The method involves slowing a velocity of fluids entering the filter cartridge of the Y strainer by having the fluids pass from a first bore of a first diameter into a second bore of a second diameter which is at least 50% larger than the first diameter prior to entering the filter cartridge. The filter cartridge also has the second diameter. This modification has been found to dramatically improve the performance of the Y strainer.

What is claimed is: 
     
       1. A method of increasing efficiency of a Y strainer having a filter cartridge receiving inflow through one end and outflow through apertures in a peripheral sidewall, the method comprising:
 slowing a velocity of fluids entering the filter cartridge of the Y strainer by having the fluids pass from a first portion of a first diameter into a second portion of a second diameter which is at least 50% larger than the first diameter prior to entering the filter cartridge, the filter cartridge being inserted into a filter cartridge receiving pipe in fluid communication with the second portion, the filter cartridge receiving pipe having the second diameter, wherein the filter cartridge has an inner sleeve with flow apertures and a flexible mesh filter which is retained between the inner sleeve and the peripheral sidewall; 
 wherein the velocity of fluids entering the filter cartridge of the Y strainer is further slowed by positioning a deflector plate supported at an inlet end of the filter cartridge and extending into the filter cartridge at an acute angle to the inlet end of the filter cartridge such that a major portion of the fluids flowing along an inlet pipe strike the deflector plate and are deflected into the filter cartridge. 
 
     
     
       2. The method of  claim 1 , wherein the deflector plate forms part of the filter cartridge. 
     
     
       3. A Y strainer assembly, comprising:
 an inlet pipe having a first portion of a first diameter and a second portion of a second diameter that is at least 50% larger than the first diameter; 
 an outlet pipe having a first portion of the first diameter and a second portion of the second diameter; 
 a cartridge receiving pipe of the second diameter in fluid communication with the second portion of the inlet pipe and the second portion of the outlet pipe, such that fluids may only pass from the inlet pipe into the cartridge receiving pipe and from the cartridge receiving pipe into the outlet pipe, the cartridge receiving pipe having a closure which can be opened to facilitate insertion of a filter cartridge; and 
 a filter cartridge having an inlet at an inlet end for receiving an inflow of fluids from the inlet pipe and apertures in a peripheral sidewall through which an outflow of fluids pass into the outlet pipe, wherein the filter cartridge has an inner sleeve with flow apertures and a flexible mesh filter which is retained between the inner sleeve and the peripheral sidewall; and 
 a deflector plate supported at the inlet end of the filter cartridge and extending into the filter cartridge at an acute angle to the inlet end of the filter cartridge such that a major portion of the fluids flowing along the inlet pipe strike the deflector plate and are deflected into the filter cartridge. 
 
     
     
       4. The Y strainer assembly of  claim 3 , wherein the inlet end of filter cartridge defines a wedge which is wedged into the inlet pipe to make a connection through which fluids flow from the inlet pipe into the filter cartridge. 
     
     
       5. The Y strainer assembly of  claim 3 , wherein an upstream sensor is positioned in the inlet pipe upstream of the filter cartridge and a downstream sensor is positioned in the outlet pipe downstream of the filter cartridge, a differential in output between the upstream sensor and the downstream sensor providing an indication of sand accumulation within the filter cartridge. 
     
     
       6. The Y strainer assembly of  claim 3 , wherein a blow down valve is positioned in the closure of the cartridge receiving pipe through which sand accumulations on the filter cartridge may be purged. 
     
     
       7. The Y strainer assembly of  claim 3 , wherein valves are positioned on the inlet pipe and the outlet pipe. 
     
     
       8. The Y strainer assembly of  claim 3 , wherein at least one valve is attached to the cartridge receiving pipe through which sand accumulations on the filter cartridge may be purged. 
     
     
       9. The Y strainer assembly of  claim 8 , wherein two valves are attached to the cartridge receiving pipe. 
     
     
       10. The Y strainer assembly of  claim 9 , wherein the valves are a ball valve and a choke valve. 
     
     
       11. The Y strainer assembly of  claim 8 , wherein a blow down opening is positioned centrally in the cartridge receiving pipe. 
     
     
       12. The Y strainer assembly of  claim 8 , wherein a blow down opening is positioned off center along a lower side of the cartridge receiving pipe.